Switch zoning limitations for the HDS USP and NSC

The Storwize® V3500 system and the HDS USP or NSC have limitations in switch zoning.

The Storwize V3500 system can be connected to the HDS USP or NSC with the following restrictions:

  • If an LU is mapped to a system port as LUN x, the LU must appear as LUN x for all mappings to target ports.
  • Only Fibre Channel connections can be used to connect the Storwize V3500 system to the HDS USP or NSC system.
  • The system limits the number of worldwide node names (WWNNs) for each storage system and the HDS USP and NSC present a separate WWNN for each port. Because of these circumstances, the number of target ports that the system can resolve as one storage system is limited. To provide connections to more target ports, complete the following steps:
    1. Divide the set of target ports into groups of 2 to 16.
    2. Assign a discrete set of LUs to each group.
    The system can then view each group of target ports and the associated LUs as separate HDS USP or NSC systems. You can repeat this process to use all target ports.
Note: The HDS USP and NSC systems present themselves to the Storwize V3500 clustered system as separate controllers for each port zoned to the Storwize V3500 system. For example, if one of these storage systems has four ports that are zoned to the system, each port appears as a separate controller rather than one controller with 4 WWPNs. In addition, a given logical unit (LU) must be mapped to the system through all controller ports that are zoned to the system by using the same logical unit number (LUN).

Controller splitting

You can split the HDS USP or NSC between other hosts and the system under the following conditions:
  • A host cannot be simultaneously connected to both an HDS USP or NSC and the Storwize V3500 system.
  • Port security must be enabled for target ports that are shared.
  • An LU that is mapped to the system cannot be simultaneously mapped to another host.